Schism

There is some question as to whether the Pope can be in actual schism as per the Cardinal Torquemada:

Citing the doctrine of Pope Innocent III, Torquemada further teaches: 

"Thus it is that Pope Innocent III states [De Consuetudine] that, it is necessary to obey the Pope in all things as long as he, himself, does not go against the universal customs of the Church, but should he go against the universal customs of the Church, 'he need not be followed' . . . " [Cited from A Theological Vindication of Roman Catholic Traditionalism, Father Paul Kramer, B.Ph., S.T.D., M. Div. (2nd edition, St. Francis Press, India) p. 29. The full quotation from Cardinal Torquemada reads, "By disobedience, the Pope can separate himself from Christ despite the fact that he is head of the Church, for above all, the unity of the Church is dependent on its relationship with Christ. The Pope can separate himself from Christ either by disobeying the law of Christ, or by commanding something that is against the Divine or natural law." It follows, then, that if it is possible for a Pope to command something against Divine law, then it is likewise possible for a Pope to permit something that is against Divine or natural law, or go against the traditional teaching of the Church. Cardinal Torquemada continues: "By doing so, the Pope separates himself from the body of the Church because the body is itself linked to Christ by obedience. In this way the Pope could, without doubt, fall into schism... (A Theological Vindication of Roman Catholic Traditionalism, Fr. Kramer)

Comparing this with the Summa and Canon Law there appears to be a contradiction - since it is quite clear that the Pope can not refuse submission to himself.

I answer that, As Isidore says (Etym. viii, 3), schism takes its name "from being a scission of minds," and scission is opposed to unity. Wherefore the sin of schism is one that is directly and essentially opposed to unity. For in the moral, as in the physical order, the species is not constituted by that which is accidental. Now, in the moral order, the essential is that which is intended, and that which results beside the intention, is, as it were, accidental. Hence the sin of schism is, properly speaking, a special sin, for the reason that the schismatic intends to sever himself from that unity which is the effect of charity: because charity unites not only one person to another with the bond of spiritual love, but also the whole Church in unity of spirit.
Accordingly schismatics properly so called are those who, wilfully and intentionally separate themselves from the unity of the Church; for this is the chief unity, and the particular unity of several individuals among themselves is subordinate to the unity of the Church, even as the mutual adaptation of each member of a natural body is subordinate to the unity of the whole body. Now the unity of the Church consists in two things; namely, in the mutual connection or communion of the members of the Church, and again in the subordination of all the members of the Church to the one head, according to Colossians 2:18-19: "Puffed up by the sense of his flesh, and not holding the Head, from which the whole body, by joints and bands, being supplied with nourishment and compacted, groweth unto the increase of God." Now this Head is Christ Himself, Whose viceregent in the Church is the Sovereign Pontiff. Wherefore schismatics are those who refuse to submit to the Sovereign Pontiff, and to hold communion with those members of the Church who acknowledge his supremacy.

http://www.newadvent.org/summa/3039.htm

Canon Law (1983)

Can. 751 Heresy is the obstinate denial or doubt, after baptism, of a truth which must be believed by divine and catholic faith. Apostasy is the total repudiation of the christian faith. Schism is the withdrawal of submission to the Supreme Pontiff or from communion with the members of the Church subject to him.(Source)

I further understand that this canon is substantially the same as the earlier (1910) code of canon law.

So if we assume that the word `schism` means the same thing in all three references, there is a clear contradiction.

However, that would be a bad assumption since we find the following in the Catholic Encyclopedia article on Schism:

Schism (from the Greek schisma, rent, division) is, in the language of theology and canon law, the rupture of ecclesiastical union and unity, i.e. either the act by which one of the faithful severs as far as in him lies the ties which bind him to the social organization of the Church and make him a member of the mystical body of Christ, or the state of dissociation or separation which is the result of that act. ... Thus understood, schism is a genus which embraces two distinct species: heretical or mixed schism and schism pure and simple. The first has its source in heresy or joined with it, the second, which most theologians designate absolutely as schism, is the rupture of the bond of subordination without an accompanying persistent error, directly opposed to a definite dogma. This distinction was drawn by St. Jerome and St. Augustine. "Between heresy and schism", explains St. Jerome, "there is this difference, that heresy perverts dogma, while schism, by rebellion against the bishop, separates from the Church. Nevertheless there is no schism which does not trump up a heresy to justify its departure from the Church (In Ep. ad Tit., iii, 10). And St. Augustine: "By false doctrines concerning God heretics wound faith, by iniquitous dissensions schismatics deviate from fraternal charity, although they believe what we believe" (On Faith and the Creed 9). But as St. Jerome remarks, practically and historically, heresy and schism nearly always go hand in hand; schism leads almost invariably to denial of the papal primacy.
Schism, therefore, is usually mixed, in which case, considered from a moral standpoint, its perversity is chiefly due to the heresy which forms part of it. In its other aspect and as being purely schism it is contrary to charity and obedience; to the former, because it severs the ties of fraternal charity, to the latter, because the schismatic rebels against the Divinely constituted hierarchy. However, not every disobedience is a schism; in order to possess this character it must include besides the transgression of the commands of superiors, denial of their Divine right to command. On the other hand, schism does not necessarily imply adhesion, either public or private, to a dissenting group or a distinct sect, much less the creation of such a group. Anyone becomes a schismatic who, though desiring to remain a Christian, rebels against legitimate authority, without going as far as the rejection of Christianity as a whole, which constitutes the crime of apostasy.
Formerly a man was rightly considered a schismatic when he disregarded the authority of his own bishop; hence the words of St. Jerome quoted above. Before him St. Cyprian had said: "It must be understood that the bishop is in the Church and the Church in the bishop and he is not in the Church who is not with the bishop" (Epist., lxvi, 8). Long before, St. Ignatius of Antioch laid down this principle: "Where the bishop is there is the community, even as where Christ is there is the Catholic Church" (Smyrnæans 8.2). Now through the centralizing evolution which emphasizes the preponderant rôle of the sovereign pontiff in the constitution of ecclesiastical unity, the mere fact of rebelling against the bishop of the diocese is often a step toward schism; it is not a schism in him who remains, or claims to remain, subject to the Holy See. In the material sense of the word there is schism, that is rupture of the social body, if there exist two or more claimants of the papacy, each of whom has on his side certain appearances of right and consequently more or less numerous partisans. But under these circumstances good faith may, at least for a time, prevent a formal schism; this begins when the legitimacy of one of the pontiffs becomes so evident as to render adhesion to a rival inexcusable. Schism is regarded by the Church as a most serious fault, and is punished with the penalties inflicted on heresy, because heresy usually accompanies it. These are: excommunication incurred ipso facto and reserved to the sovereign pontiff (cf. "Apostolicæ Sedis", I, 3); this is followed by the loss of all ordinary jurisdiction and incapacity to receive any ecclesiastical benefices or dignities whatsoever. To communicate in sacris with schismatics, e.g., to receive the sacraments at the hands of their ministers, to assist at Divine Offices in their temples, is strictly forbidden to the faithful.
Some theologians distinguish "active" from "passive" schism. By the former they understand detaching oneself deliberately from the body of the Church, freely renouncing the right to form a part of it. They call passive schism the condition of those whom the Church herself rejects from her bosom by excommunication, inasmuch as they undergo this separation whether they will or no, having deserved it. Hence, this article will deal directly only with active schism, which is schism properly so-called. It is nevertheless clear that so-called passive schism not only does not exclude the other, but often supposes it in fact and theory. From this point of view it is impossible to understand the attitude of Protestants who claim to hold the Church they abandoned responsible for their separation. It is proved by all the historical monuments and especially by the writings of Luther and Calvin that, prior to the anathema pronounced against them at the Council of Trent, the leaders of the Reformation had proclaimed and repeated that the Roman Church was "the Babylon of the Apocalypse, the synagogue of Satan, the society of Antichrist"; that they must therefore depart from it and that they did so in order to re-enter the way of salvation. And in this they suited the action to the word. Thus the schism was well consummated by them before it was solemnly established by the authority which they rejected and transformed by that authority into a just penal sanction. (Catholic Encyclopedia)

 My conclusion is that Cardinal Torquemada was referring to heretical schism.